title: Development, validation, and results of a measure of 30-day readmission following hospitalization for pneumonia.
abstract: BACKGROUND
  Readmission following hospital discharge has become an important target of quality improvement.
  
  
  OBJECTIVE
  To describe the development, validation, and results of a risk-standardized measure of hospital readmission rates among elderly patients with pneumonia employed in federal quality measurement and efficiency initiatives.
  
  
  METHODS
  A retrospective cohort study using hospital and outpatient Medicare claims from 2005 and 2006.
  
  
  METHODS
  A total of 4675 hospitals in the United States.
  
  
  METHODS
  Medicare beneficiaries aged >65 years with a principal discharge diagnosis of pneumonia.
  
  
  METHODS
  None.
  
  
  METHODS
  Hospital-specific, risk-standardized 30-day readmission rates calculated as the ratio of predicted-to-expected readmissions, multiplied by the national unadjusted rate. Comparison of the areas under the receiver operating curve (ROC) and measurement of correlation coefficient in development and validation samples.
  
  
  RESULTS
  The development sample consisted of 226,545 hospitalizations at 4675 hospitals, with an overall unadjusted 30-day readmission rate of 17.4%. The median risk-standardized hospital readmission rate was 17.3%, and the odds of readmission for a hospital one standard deviation above average was 1.4 times that of a hospital one standard deviation below average. Performance of the medical record and administrative models was similar (areas under the ROC curve 0.59 and 0.63, respectively) and the correlation coefficient of estimated state-specific standardized readmission rates from the administrative and medical record models was 0.96.
  
  
  CONCLUSIONS
  Rehospitalization within 30 days of treatment for pneumonia is common, and rates vary across hospitals. A risk-standardized measure of hospital readmission rates derived from administrative claims has similar performance characteristics to one based on medical record review.
authors.affiliation: Center for Quality of Care Research, Baystate Medical Center, Springfield, Massachusetts 01199, USA. peter.lindenauer@baystatehealth.org
authors.forename: Peter K
authors.initials: PK
authors.lastname: Lindenauer
authors.forename: Sharon-Lise T
authors.initials: SL
authors.lastname: Normand
authors.forename: Elizabeth E
authors.initials: EE
authors.lastname: Drye
authors.forename: Zhenqiu
authors.initials: Z
authors.lastname: Lin
authors.forename: Katherine
authors.initials: K
authors.lastname: Goodrich
authors.forename: Mayur M
authors.initials: MM
authors.lastname: Desai
authors.forename: Dale W
authors.initials: DW
authors.lastname: Bratzler
authors.forename: Walter J
authors.initials: WJ
authors.lastname: O'Donnell
authors.forename: Mark L
authors.initials: ML
authors.lastname: Metersky
authors.forename: Harlan M
authors.initials: HM
authors.lastname: Krumholz
mesh_terms: D000368:Aged; D015331:Cohort Studies; D005260:Female; D006760:Hospitalization / Q000639:trends; D006801:Humans; D008297:Male; D008499:Medical Records; D006278:Medicare / Q000592:standards / Q000639:trends*; D008875:Middle Aged; D010359:Patient Readmission / Q000592:standards / Q000639:trends*; D011014:Pneumonia / Q000453:epidemiology / Q000628:therapy*; D012189:Retrospective Studies; D014481:United States / Q000453:epidemiology